Rotary web cutter and stripper assembly



7 A e RN a ROTARY WEB CUTTER AND STRIPPER ASSEMBLY Oct. 11, 1966 United States Patent O 3,277,756 ROTARY WEB CUTTER AND STRIPPER ASSEMBLY James Des Jardins, Chicago, and Richard J. Fowich, Elm

hurst, Ill., assignors to R. R. Donnelley & Sons Company, a corporation of Delaware Filed Apr. 22, 1965, Ser. No. 449,969 8 Claims. (Cl. 83-116) This invention relates to printing presses and more particularly to the web severing mechanisms associated therewith.

-In the press rooms of all major printing operations a very high level of noise is present whenever the presses are running. It has been found that this high level of noise contributes immeasurably to fatigue, loss of hearing and other associated conditions of the nervous system of employees forced to be present in the press room for protracted periods of time. Considerable effort has been and is being put forth to reduce the various sources of noise that contribute to the over-all high noise level. This invention is directed primarily to substantially eliminating the noises created during operation of high speed presses by the engagement and disengagement of the hard cheek blocks of the cutter cylinder against the backing block of the mating folding cylinder as printed webs of paper are cut to sheet lengths.

Heretofore, the cheek blocks on either side of the cutting knives have generally been made of wood, canvas impregnated with phenolic material, or hard plastic, and have been resiliently urged forward by springs, hydraulics or other biasing means.- As the cutting cylinders with the cutting knives rotate relative to the mating folding cylinders, the cheek blocks engage with the hard surface of the mating folding cylinder and are forced back, causing considerable noise. After the cut takes place the spring or other biasing means drives the cheek blocks toward their fully extended positions relative to the cutting knife, and the stops on the cheek blocks bang against their stops on the cutting cylinder, adding further noise to the operation. These two sets of noises from the cheek block are repeated many hundreds of times a minute which contributes substantially to the high noise level of the press room.

A principal object of the present invention, therefore, is to eliminate or greatly reduce the above described noises and thereby reduce the over-all operating noise of the press.

Another object of the invention is to provide a cheek block construction using noise deadening material in place of the previously used noise creating material.

Still another object of the invention is to provide a cheek block construction in which the inherent resiliency of the cheek block material serves to wipe the knife blade during disengagement Iof the blade from the folding cylinder without the need for separate biasing means.

And yet another Iobject of the invention is to provide a construction that permits replacement of the cheek blocks to be accomplished Without requiring special tools.

. Another object of the invention is to provide an improved cheek block construction that is much less expensive to manufacture and maintain than are the structures heretofore commonly used.

Still another object of the invention is to provide an improved cheek block arrangement in which the web or sheet impaling pins chew out or cut out their own clearance openings in the trailing edge of the rearward cheek block, further reducing the cost of the assembly.

Still a further object of the invention is to provide a cheek block arrangement wherein movement of the blocks relative to the blade is accomplished in such a'way as to minimize Wear both on the block and on the knife blade.

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These and other objects, features -and advantages of the present invention will be apparent from the following detailed description taken in connection with the accompanying drawing, in which:

FIG. 1 is a cross-sectional view taken through a portion of the cutting couple constructed according to the invention;

FIG. 2 is a cross-sectional view similar to FIG. 1 but showing the relative positions of the cutting couple just prior to the cutting phase of the cycle; and

FIG. 3 is a top view of the cutting portion of the cutting cylinder showing the cheek blocks in position relative to the cutting blade.

FIG. 1 and FIG. 2 illustrate the cutting couple of a printing press, and in particular of a high speed printing press, which comprises a folding cylinder 12 cooperating with a mating cutting cylinder 13 that are provided, respectively, with a female cutting block 14 and knife blade 15 between which a paper web W passes. The knife 15 severes the web W into predetermined sheet lengths as the cylinders 12 and 13 rotate. The cylinders 12 and 13 are driven by -conventional power means on the printing press. One or more knives 15 may be positioned in the surface of the cylinder 13 along axes parallel to the axis of the cylinder 13 and are circumferentially spaced apart a predetermined distance to effect the desired length of cut in the paper web W.

At each cutting station in the cutting cylinder 13 there is provided a longitudinal slot or groove 16 having a substantially rectangular bottom and lying along an axis substantially parallel to the axis of the cylinder. The slot 16 extends lgenerally from one end of the cylinder to the other. In each slot or groove 16 is seated a knife box 18 comprising a pair of mating halves or side portions 20, 21 having coplanar surfaces 22 and 23 that form the bottom wall of the box, and planar mating surfaces 22a, 23a that ankingly abut the bottom portion of the knife blade 15 throughout the full length of the blade. The two halves of the knife box 18 and the bottom portion of the knife 15 are seated in the groove 16 and are secured therein by rneans of adhesive, keys, set screws or any other known fastening means. The knife box 18 has side walls 25 and 26 provided with inwardly projecting portions 27, 28, respectively, near the cutting edge of the blade so as to provide overhanging portions 30, 31 that dene an undercut or recessed cavity .on each side of the knife blade 15. The projecting portions 27, 28 of the knife box 18 define an opening 32 through which the knife blade 15 extends and through which access is gained to the cavities in said box.

A leading cheek block 33 and a trailing cheek block 34 are seated in the knife box 18 on opposite sides of the knife blade 15. Leading cheek block 33 has an extended wiping portion 35 and a rectangularly shaped anchor portion 36 formed integrally therewith. The wiping portion 35 has one side bearing against the blade and has the other or outer side tapered so as t-o form a relatively thick juncture with the anchor portion and relatively narrow unbroken end -surface 39. The rectangularly shaped anchor portion 36 of the cheek block has a cut out section 40 formed in its outer side wall which extends throughout the length of said anchor portion.

The trailing cheek block 34 is lconstructed in exactly the same manner as block 33 but is lreversed to provide an oppositely facing tapered wiping portion 35a and an anchor portion 36a. A slot 40a is likewise formed in the side wall of the block 34.

The radial dimension or depth Iof the cheek blocks is slightly greater than the depth of the knife box from the bottom wall 22, 23 to the surface of the cylinder 13, so the cheek blocks project radially a short distance from the cylinder surface.

The cheek blocks 33, 34 are an elastomer having a durometer hardness of 35 i5, and are preferably pure natural rubber. It has been found that natural rubber produceslhe/rnost desirable results in the present apparatus, because it has a long life, a high resiliency rate, a natural biasing frequency eliminating the need for any supplemental springs, is quiet in operation, and fwhen properly used will 4not -leave marks on the paper. The cheek block may be formed 'by extrusion.

A pair of cheek blocks 33, 34 may be easily installed or replaced in the knife box 18 by removing the knife box 18 from the groove 16 in the cutting cylinder, unbolting the two halves 20 and 21 and removing the old cheek blocks. A new pair of cheek blocks 33, 34 and either a new or a resharpened knife blade 15 are then assembled together with the cheek blocks bearing against opposite sides of the knife blade 15. The anchor portions 36, 36a are seated in the cavities in the halves of the knife box 18 whereupon the halves are bolted together to form an operative cutter unit. The knife box with the blade 15 and cheek blocks 33, 34 is then reassembled in the groove 16 in the cutting cylinder whereupon the press is ready to roll again. The extended or wiping portions 35 and 35a of the cheek blocks bear against the opposite surfaces of the cutting edge portions of the knife blade 15 for supporting the cutting edge in its transverse position relative to the surface of the cutting cylinder. The cut out portions 40l in the cheek blocks serve the function of providing spaces into which the material of thev anchor portions expands, particularly during displacement of the wiping portions 35, 35a during a cutting stroke of the cutting couple. Were the anchor portions completely enclosed, they would be relatively inflexible, and the cut outs 40 permit the material to deform and ilex more readily.

The mating or folding cylinder 12 has the cutting block or member 14 anchored in a rectangular longitudinal groove 43 which extends along yan axis substantially paral- Ilel to the axis of the cylinder 12 in the surface portion of said cylinder. The block 14 has an undercut groove or slot 45 formed throughout its length which is adapted to receive in nesting relationship the cutting edge portion of the cutting blade 15. The cutting slot 45 has an opening 46 extending across the face of the block 14, which opening is defined by a pair of edges 47 and 48'. With the paper web W stretched across the opening 46, the cutting edge of the blade may engage the opposite side of the paper between the edges 47, 48 so that as the knife penetrates into the slot 45, the cut or slice of the web W takes place. A plurality of impaling pins 49 are positioned throughout the length of said block 14 in a position ust to the trailing edge of said block. The pins 49 extend a short distance radially from the face of the folding cylinder and are adapted to impale the uncut web 12 for holding the Web in position throughout the cutting operation and -for pulling the web through the cutting position of the cycle.

The trailing cheek block 34 is provided with an unrelieved upper marginal portion 39 which is adapted during the initial stages of operating a new pair of cheek blocks 33, 34 to be chewed or cut by the impaling pins 49 along said unrelieved marginal portion 39. A plurality of small appropriately sized chewed out portions 50 are soon formed throughout the length of the upper marginal edge portion of the cheek block 34 as can be best seen in FIG. 3. The trailing half 21 of the knife box 18 has Ia plurality of grooves 52 cut through its top surface 53 in spaced relationship and in substantial alignment with the chewed out portions 50 of the cheek block. These notches or grooves 52 are cut in the box in a slightly oversized sha-pe prior to the knife box 18 being installed in the 'groove 16 in the cutting cylinder 13 and a-re made to align with the impaling pins 49 so as not to interfere with lthe action of the impaling pins and still to provide a backing surface for the sheet of paper and for the impaling pins as the pins sweep through their path of movement.

lt is now believed to be clear that with the cheek blocks 36 and 34 marde of an extrusion of natural rubber, the Contact noise caused by the mating contacts between the cheek blocks and the folding cylinder and between the cheek blocks and the portions of the knife box of the cutting cylinder is substantially eliminated.

The wiping portions 35 of the cheek blocks 33, 34 are displaced each time a cut is performed by the knife, due to the engagement of the faces of the mating block 45 with the unrelieved upper marginal portions 39 of the cheek blocks. As the cylinders pass beyond the cutting position the resiliency of the natural :rubber in the cheek blocks wipes the paper from the knife blade 15 as the blade continues into its next cutting position. The natural biasing frequency of the rubber cheek blocks eliminates the need for separate biasing means to unge the marginal edges of the blocks to their initial position. The anchor portions of the blocks 33, 34 substantially fil-l the cavity in the box 18 so that there is no free movement of the block in the box.

We claim:

1. A cheek block for use with a cutting couple of a printing press, comprising: a body member consisting of an elastomer that has a durometer hardness of 35i5, said body member having an anchor portion and a wiping portion, said anchor portion being adapted to fit in a mounting cavity in a cutting cylinder and having a cut out portion which permits a degree of deformation greater than the natural deformation of said portion, and said wiping portion extending along an axis outwardly from said anchor portion and having an outer end lying substantially transverse to said axis.

2. The cheek block of claim 1 which consists of substantially pure natural rubber.

3. The cheek block of claim 1 in which the wiping portion is tapered from a relatively thick section near the anchor portion to a relatively thin outer end.

4. A cheek block foruse with a cutting couple of a printing press, comprising an elongate body member having an anchor portion and a wiping portion integrally formed therewith, said anchor portion having at least one substantially square corner near the juncture of said anchor portion with said wiping portion, cut out means in said anchor portion for permitting said anchor portion to be distorted an amount greater than the normal distortion of the material of said body member, and said wiping portion being tapered from a relatively thick section near said anchor portion to a relatively thin outer edge.

5. In a cutter for a rotary printing press, in combination: a cutting cylinder having -a continuous longitudinal groove; a knife box secured in said groove, said knife box having side portions which terminate substantially ush with the cylinder surface and which have facing parallel walls; a cutting blade in said knife box which is parallel to said facing walls and generally on the median plane of the space therebetween, said blade projecting radially a short distance outside the cylinder surface; and a pair of resilient cheek blocks removably secured in said knife box flanking said blade, each of said blocks having a lower anchor portion which lits snugly between the blade and one of the facing Walls of the knife box and having an upper wiping portion which contacts the blade, tapers away from said one of the facing walls, and has an outer end outside the cylinder surface but inside the edge of the blade, said tapered wiping portions of said cheek blocks providing a close wiping fit for the blade and affording clearance spaces from the facing knife box walls so that said blocks may depress and deform freely during a cutting operation.

6. The combination of claim 5 in which the cheek blocks have a durometer hardness of 35 l 5.

7. The combination of claim 6 in which the cheek blocks are pure natural rubber.

5 8. The combination of -clairn 5 in which the anchor portions of the cheek blocks have lognitudinal grooves facing the knife box Walls to permit `a degree of deformation greater than the natural deformation of said anchor portions.

References Cited by the Examiner UNITED STATES PATENTS 6 1,977,283 10/ 1934 Lundquist 83-347 2,450,312 9/ 1948 Tollison 83-139 FOREIGN PATENTS 620,241 3/ 1949 Great Britain.

WILLIAM W. DYER, J R., Primary Examiner.

L. TAYLOR, Assistant Examiner. 

1. A CHEEK BLOCK FOR USE WITH A CUTTING COUPLE OF A PRINTING PRESS, COMPRISING: A BODY MEMBER CONSISTING OF AN ELASTOMER THAT HAS A DUROMETER HARDNESS OF 35+5, SAID BODY MEMBER HAVING AN ANCHOR PORTION AND A WIPING PORTION, SAID ANCHOR PORTION BEING ADAPTED TO FIT IN A MOUNTING CAVITY IN A CUTTING CYLINDER AND HAVING A CUT OUT PORTION WHICH PERMITS A DEGREE OF DEFORMATION GREATER THAN THE NATURAL DEFORMATION OF SAID PORTION, AND SAID WIPING PORTION EXTENDING ALONG AN AXIS OUTWARDLY FROM SAID ANCHOR PORTION AND HAVING AN OUTER END LYING SUBSTANTIALLY TRANSVERSE TO SAID AXIS. 